Gas-holder



EIJ-fEEicE.

PATENT CHARLES e. EAIRCHILD, or OBERLIN, onto.

GAS-HOLDER.

SPECIFICATION forming part of Letters Patent No. 357,276, dated February 8, 1887.

Applica tion filed January 26, 18E6. Serial No.189,834. (No model.) l

To @ZZ whom zit may concern:

Be it known that- I, CHARLES G. FAIRCHILD, a citizen of the United States, and a resident of Oberlin, in the county of Lorain and State of Ohio, have invented certain new and use ful Improvements in Gas-Holders, of which the following is a specification.

My invention relates tov that class of gasliolders employed for use with portable apparatus-as, for instance, with chemical apparatus used in public lectures, stereopticons, 8vo.; and my invention consists of a bag combined with a contractile envelope, so constructed as to increase its contractile force rin proportion as the bag is expanded,and to reduce its force as the area of the bag is contracted, so as to maintain a uniform pressure upon the gas within the bag, however the volume of the gas may increase or diminish.

In the drawings, Figure l is an external .view of my improved gaseholder, illustrating one form of envelope. Fig. 2 isa transverse section of a holder and support, illustrating another form of contractile envelope. Fig. 3 is an external view of a holder, illustrating a third form of envelope. Fig. 4 is a transverse section .on the line l 2, Fig. 3. Fig.\5 is the same view asFig. 4, showing the holder contracted.

rlhe gas holder or receptacle A is preferably in the form of a cylindrical bag having rounded ends, one of which is provided with a neck, b, for connection with the supply and discharge tube d, the bag being formed of any flexible material impervious to gas-as, for instance, of lrubber fabric. To the bag is applied a contractile envelope, which may loe formed in various ways, so that' as the gas is introduced into the bag under pressure and the latter is expanded the envelope will yield, but will increase its resistance to the expansion of the bag in proportion as the latter increases in size, and conversely the saidA contractile envelope will contract with greater force when the bag is full of gas,and its contractile power will decrease in proportion as the quantity of gas in the 'bag is diminished. By this means a practically-uniform pressure upon the gas is secured, so that it is`not necessary to use a regulating apparatus and vary the latter from time to time as the gas becomes exhausted.

This uniform action results from the fact that while the contractile force of the envelope is greater when the bag is full of gas the internal area of the bag is also greatest at such time, and that as the bag collapses and the contract-r ile force of the envelope diminishes the internal arca of the surface of the bagA also diminishes.

One of the methods of Vconstructing the contractile envelope is illustrated in Fig. 1,which shows the bag Aas inclosed in a net consisting of crossed bands or cords of rubber, the envelope contracting to force out lthe gas, and also simultaneously contracting the bag,bring ing the sides thereof together and reducing the area of the internal surface.

Another means of securinga contractile envelope is illustrated in Fig. 2, which shows the bag as supported upon a grooved table or platform, D, with parallel ribs f,of wood or other suitable substance, arranged upon the outside of the bag, andwith cords or bands g, each passing round a guide-roller, h, encircling the bag, and passing around another guide-roller, t', adjacent to the roller h, and each connected to a spring, j.

When the bag is contracted to the dimensions illustrated in dotted lines, Fig. 2, the springs j are also contracted and exert but little force, and as the bag expands and widens the loops of cord or bands composing the same the springs j are distended and their resistance increases. Vhen the bag is being exhausted/the power of the springs j decreases in proportion as the dimensions of the bag are contracted by the contraction of the encircling loops.

A preferable construction of the envelope is shown in Figs. 3, 4, and 5, in which rubber 9c bands m are used to encircle the bag and the ribs f applied thereto, the expansion of the bag being accompanied by a constantly-inE creased resistance of the bands, andthe dimensions of the bag decreasing as the bands become weakened. rlhis construction is attended with a great advantage, resulting from the ease with which the compressive power of the gasholder may be increased or diminished by adding to or reducing the number of bands applied to the holder.

The above-described gas-holder maybe used IOO for any of the purposes for which gas-l1olders are ordinarily employed-21s, for instance, in laboratories, for stereopticons, public chemical experiments, and other purposes.

I do not claim, broadly, a bag inclosed by isolated elastic bands, myinvention being distinguished from such an arrangement by the use of an envelope which presses on all sides of the bag to expel the contents with the same effect as when a at Weighted board is used.

lithout limiting myself to the precise construction and arrangement of parts shown, I claim- 1. The combination of a Ilexible bag and an envelope of elastic material inclosing the bag throughout its length capable ofyielding as the CHARLES G. FAIRCHILI).

Witnesses:

CHAs. B. L'nx, IRAL A. WEBSTER. 

